The present inventive concepts relate to Global Navigation Satellite System (GNSS) receivers, and more particularly to reducing or otherwise minimizing power consumption in GNSS receivers.
Thousands of satellites have been launched into space. Some of these satellites are used in satellite navigation systems. A satellite navigation system having global coverage is referred to as a global navigation satellite system (GNSS). The United States NAVSTAR Global Positioning System (GPS) and the Russian GLONASS are each examples of an operational GNSS.
Satellite navigation systems provide location and time information. Small mobile electronic devices on Earth having embedded GNSS receivers can acquire a “position fix” when an unobstructed line of sight is available to multiple satellites. Such devices can include, for example, a smart phone, a camera, a mobile computer, a GPS logger, a mobile device, and the like. Power consumption of a GNSS receiver is a substantial portion of the overall power budget of the device when in use. High power consumption is problematic because mobile devices are generally powered using batteries, and battery life of the devices is impacted by processing activities associated with obtaining the position fix.
Conventional GNSS receiver technology includes techniques that sequence, usually periodically, through GNSS receiver ON/OFF cycles. For example, the GNSS receiver may implement “trickle power” or active continuous track (ACT) procedures. This may involve, for example, turning the GNSS receiver on for a fixed period of time such as 10 milliseconds (ms), then off for a fixed period of time such as 2 ms, and so forth. The repetitive on and off cycling occurs even when a position fix is not obtained. In other words, the GNSS receiver may fail to gain the orientation when turned on, which in some cases may result in incorrect assumptions. In other cases, the conventional approaches may leave the GNSS receiver turned on too long, as much as 99 ms or more, even while in the presence of strong satellite signals. Other approaches involve attempting to observe the signal strength of one satellite at a time. Such approaches result in disadvantageous resource waste and unnecessary power consumption.
What is needed is an improved apparatus and method for reducing power consumption in electronic receivers, and in particular, GNSS receivers. Together with related inventive concepts disclosed herein, these and other limitations in the prior art are addressed.